Annual Fossil-Fuel CO2 Emissions: Isomass of Emissions Gridded by One Degree Latitude by One Degree Longitude R.J. Andres, T.A. Boden, and G. Marland Carbon Dioxide Information Analysis Center, Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6335, U.S.A. DOI: 10.3334/CDIAC/ffe.db1013.2009 Period of Record ---------------- 1751-2006 Methods ------- The basic data provided in these data files are derived from time series of Global, Regional, and National Fossil-Fuel CO2 Emissions (http://cdiac.ornl.gov/trends/emis/overview_2006.html) and references therein. The data accessible here take these tabular, national, mass-emissions data, multiply them by stable carbon isotopic signature (del 13C) as described in Andres et al. (2000), and distribute them spatially on a one degree latitude by one degree longitude grid. The within-country spatial distribution is achieved through a fixed population distribution as reported in Andres et al. (1996). Note that the mass-emissions data used here are based on fossil-fuel consumption estimates as these are more representative of within country emissions than fossil-fuel production estimates (see http://cdiac.ornl.gov/faq.html#Q10 for a description why emission totals based upon consumption differ from those based upon production). Data File Structure and Naming Convention ----------------------------------------- There is a separate data file for each year. The files have a basename of gridiso and an extension of yyyy where yyyy is the year (e.g., 2000). The unit of the mass data portrayed is 10E6 metric tonnes * per mil of C or Tg * per mil C (Tg=10E12 g). To calculate the del 13 C signature in each grid cell, divide the values reported here by the corresponding grid cell value in Annual Fossil-Fuel CO2 Emissions: Mass of Emissions Gridded by One Degree Latitude by One Degree Longitude (http://cdiac.ornl.gov/epubs/ndp/ndp058/ndp058_v2009.html). Two identical sets of data are available: 1. Compressed gridiso.yyyy.Z files (one file for each year). These files were compressed using the standard unix compression utility to speed downloading. You will need to uncompress them using the unix "uncompress *" command), and 2. One tar file (gridiso.tar) file which contains all 256 files and the documentation files in a compressed state. Before using the files, users will need to extract the files from the tar file using the "tar xvf gridcar.tar" command and then uncompress the resulting files using the unix "uncompress *" command. We suggest the data should be plotted before directly incorporating the data into a model or other use. If read in correctly, the data should plot a map of the world with North at the top and East to the right. On each line, the data go from the 180-179 degrees west cell to the 179-180 degrees east cell until reading in the next line of data. In FORTRAN, the data were written with: parameter (maxlat=180, maxlon=360) C DISTRIBUTE C ON GRID do 1200, i=1, maxlat do 1200, j=1, maxlon write (14,*) gridcar (i,j) 1200 continue In addition to the annual gridiso.* files, there is one SUMMARY.ISOMASS.DAT file. This summary file contains the year, the minimum grid cell value, the maximum grid cell value, and the global del13C value. This file is included as an additional means to check that the gridiso.* files have been read correctly. References ---------- Andres R.J., Marland G., Fung I., and Matthews E. (1996) A one degree by one degree distribution of carbon dioxide emissions from fossil fuel consumption and cement manufacture, 1950-1990. Global Biogeochemal Cycles 10:419-429. Andres R.J., Marland G., Boden T., and Bischof S. (2000) Carbon dioxide emissions from fossil fuel consumption and cement manufacture, 1751-1991, and an estimate of their isotopic composition and latitudinal distribution, in Wigley T.M.L., Schimel D.S. (eds.) The Carbon Cycle. Cambridge: Cambridge University Press. 53-62. CITE AS: Andres, R.J., T.A. Boden, and G. Marland. 2009. Annual Fossil-Fuel CO2 Emissions: Isomass of Emissions Gridded by One Degree Latitude by One Degree Longitude. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A. doi 10.3334/CDIAC/ffe.db1013.2009